German cockroaches live where you cannot see them: behind the dishwasher motor, inside the fridge cavity, under the bench overhang, in the gap beside the oven. A floor spray does almost nothing to them. Gel bait into those points works, because whatever feeds carries it back. Australian and smoky brown cockroaches come in from outside through drains, weep holes and around the switchboard, so that one is a perimeter job.
Kitchen prep decides the result. Crumbs under the toaster and a wet sponge in the sink will outcompete any bait sold. You get told what to clear and what to leave alone, since wiping the treated spots afterwards undoes the visit. Student rentals around Waurn Ponds and the Deakin campus are the regular callers here.
